nfc: hci: fix out-of-bounds read in HCP header parsing

Summary

In the Linux kernel, the following vulnerability has been resolved: nfc: hci: fix out-of-bounds read in HCP header parsing Both nfc_hci_recv_from_llc() and nci_hci_data_received_cb() read packet->header from skb->data at function entry without first checking that the buffer holds at least one byte. A malicious NFC peer can send a 0-byte HCP frame that passes through the SHDLC layer and reaches these functions, causing an out-of-bounds heap read of packet->header. The same 0-byte frame, if queued as a non-final fragment, also causes the reassembly loop to underflow msg_len to UINT_MAX, triggering skb_over_panic() when the reassembled skb is written. Fix this by adding a pskb_may_pull() check at the entry of each function before packet->header is first accessed. The existing pskb_may_pull() checks before the reassembled hcp_skb is cast to struct hcp_packet remain in place to guard the 2-byte HCP message header.

Timeline

1. Jul 19, 2026, 2:55 PM UTCCVE published
2. Aug 5, 2026, 12:37 PM UTCRecord last updated

Affected versions

• Linux Linux

  Version range not reported

• Linux Linux

  3.5

References 8